In conventional gas ovens there is provided at least one gas-fueled burner which is utilized to supply heat upon demand to the oven cavity for either broiling or baking purposes. When food to be heated is placed in the oven, the operator will manually open a gas valve to allow fuel to flow to the burner where it will be ignited by an electric igniter. This will cause the burner to raise the temperature within the oven to a preset maximum level.
During a cooking cycle combustion products will be generated and will pass out of the oven through a flue and will be exhausted to the atmosphere external to the oven. When the preset maximum temperature level has been reached a thermostat will cause the gas valve to close, shutting off the supply of fuel to the burner. Consequently, the oven temperature will drop to a preset mimimum level at which the thermostat will again operate the valve, opening it to again supply fuel to the burner for raising the oven temperature. Such cycling of the burner is conventional procedure whereby an oven will be maintained at a relatively constant temperature between the preset maximum and minimum levels during the cooking process.
When the maximum preset temperature level has been reached and the burner turned off, the combustion products and air within the oven will continue to be exhausted through the flue. It will be apparent that such loss of hot air will cause the temperature of the oven to be lowered relatively quickly. Thus, the burner consequently will be reoperated much sooner than is desirable. This creates undesirable fuel consumption.